I had a small drop from about knee height and it was in a protective case. Since that time it intermittently connects but mostly is disconnected. Had sim card checked by Koodo and they say it is ok.(they put a working sim card in my phone and same problem) All it says is not connected to network, emergency calls only
Back it up. Wipe it. Reload the OS.. if it fails after that then it's likely hardware. Even with a light drop, if it lands just the right way, it's not out of the realm of possibility to jiggle something loose.